NCERT Solutions for Class 8 Science

Are you looking for NCERT solutions for class 8 Science? If yes Here, we provide the detailed solutions of the class 8 Science NCERT book! Are you tired of solving NCERT questions of class 8 Science and still not able to get accurate answers? If yes! then you are at the right place!

The NCERT solutions are provided below to assist students in answering questions correctly, using a logical and practical approach. The solutions provide sufficient resources to enable students to build a good foundation and develop the lesson's foundations. You can also familiarize yourself with the 8th Additional Class Science Questions at our website.

This page gives you all the NCERT Solutions for Class 8 Science links. You can download, Copy each chapter's Solutions to your desktop. NCERT 8th-grade science solutions are a valuable tool developed by our science experts to help students in their 8th-grade exams.

Class 8 science consists of a total of 18 chapters and these chapters are from three parts of science physics, chemistry, and biology. All three parts need a different approach to score good marks and build a good foundation. Do solve all the questions asked in the NCERT textbook with the help of NCERT Solutions for class 8 prepared by HT in an easy and lucid language all NCERT Solutions are errorless and accurate. 

• Class 8 chemistry chapters- NCERT textbook for class 8 science consists of 5 chapters from the chemistry part. To excel in these chapters, you need to start with understanding the reaction and remembering a few names of elements. Make notes of the chapter and try to remember all chemical formulas of salts used in the chapter for further studies.

1.  Chapter 3: Synthetic Fiber and Plastics
2.  Chapter 4: Materials: Metal and Non-metals
3.  Chapter 5: Coal and Petroleum
4.  Chapter 6. Combustion and Flame
5.  Chapter 7: Pollution of Air and Water

• Class 8 Physics chapters- Physics is the subject of concepts and their application in the numerical. To excel in physics, you need to understand the concepts given in the NCERT textbook and try to note down all required formulas to solve the questions given in the NCERT textbook exercise. The chapters covered in physics are.

1.  Chapter 11: Force and Pressure
2.  Chapter 12: Friction
3.  Chapter 13: Sound
4.  Chapter 14: Chemical Effects of Electric Current
5.  Chapter 15: Some Natural Phenomena
6.  Chapter 16: Light

• Class 8 Biology chapters- Biology is the subject of concept and information, it required time to understand the process. NCERT textbook explains all the chapters of biology in the required detail and uses lots of information, images, and infographic to have a clearer understanding of the subject. Chapters covered in biology are.
•  Chapter 1: Crop Production and Management
•  Chapter 2 : Microorganisms: Friend and Foe
•  Chapter 7: Conservation of Plants and Animals
•  Chapter 8: Cell Structure and Functions
•  Chapter 9: Reproduction in Animals
•  Chapter 10: Reaching the Age of Adolescence

Here are chapter Wise NCERT Solutions for Class 8 Science:

There are a total of 18 chapters in the Class 8 NCERT Book. Here, we provide the complete chapter-wise NCERT Solutions for Class 18 Science in English and Hindi.

• NCERT Solutions for Class 8 Science Chapter 1: Crop Production and Management

1.  Sustainable techniques should be followed to improve crop yield which includes.

Crop variety improvement: It is done by careful artificial selection and plant breeding techniques.

1. The genetically modified plant is made by gene manipulation.
2. The main objectives of variety improvement are high yield and improved quality, biotic and abiotic resistance, desirable agronomic characteristics, etc.

Crop production management:

1. Nutrient management, which is done by the balanced use of manures, fertilizers, biofertilizers, etc.
2. Proper irrigation method which supplies water, especially during stressful periods.
3. Healthy cropping patterns in the form of crop rotation, mixed cropping, etc.
4. Organic farming ensures minimal use of chemicals to maintain environmental and ecological stability.

Crop protection management:

1.  Weed management control is done by physical, chemical and biological methods.
2.  Pathogen and pest control are done by chemicals, but the biological control method is preferred.
3.  Storage of grains is susceptible to biotic and abiotic factors and needs preventive measures.

• NCERT Solutions for Class 8 Science Chapter 2: Microorganisms: Friend and Foe

We cannot see them, we cannot hear them but they are with us: There are about 100 trillion microorganisms in and around our bodies. The fact is that without microorganisms we would not survive. A microorganism is a living organism that is so small that it can only be seen with the aid of a microscope. The fungus that grows on the bread can be seen with a magnifying glass. Bacterial cells are about one-hundredth of the size of a human cell and viruses are much smaller.

While it is true that microorganisms are responsible for a large number of human diseases, they also make it possible for the cycle of chemical exchange between organisms and their environment. The decision as to whether bacteria are friends or foes becomes more difficult when both the positive and negative aspects of the relationship between human beings and microorganisms are considered. However, it can be concluded that bacteria can survive without us, but we would not be able to live without them.

1.  The study of microorganisms is known as microbiology.
2.  The main microorganisms are protozoa, algae, fungi, bacteria, and viruses.

• NCERT Solutions for Class 8 Science Chapter 3: Synthetic Fibers and Plastics Synthetic fibres are made from synthesized polymers or small molecules.

Depending upon the type of chemical used for manufacturing synthetic fibres, there are four major types of synthetic fibres (or man-made fibres). These are:

1.  Rayon
2.  Nylon
3.  Polyester
4.  Acrylic

Rayon is often regarded as artificial silk. It is a manufactured regenerated cellulose fibre. It is made from purified cellulose, primarily from wood pulp, which is chemically converted into a soluble compound. It is then dissolved and forced through a spinneret to produce filaments which are chemically solidified, resulting in synthetic fibres of nearly pure cellulose. Because rayon is manufactured from naturally occurring polymers, it is considered a semi-synthetic fibre. Specific types of rayon include viscose, modal and lyocell, each of which differs in manufacturing process and properties of the finished product.

• NCERT Solutions for Class 8 Science Chapter 4 : Materials: Metals and Non-Metals

Though there are millions of substances in this world, they are all made up of a limited number of basic substances, which are called elements.

You have already studied about elements as being pure substances that each are made up of one kind of atoms only. For the convenience of study, these elements are divided into two broad classes: Metals and non-metals.

This division of elements is because certain properties are found only in metals and certain others that are found only in non-metals. But some elements show the properties of both metals and non-metals. They are known as metalloids. Some common metalloids are arsenic, antimony and silicon.

The noble (inert) gases are from the fourth category of elements. The majority of the elements known to us are metals.

For examples gold, silver, platinum, copper, iron aluminium, tin, nickel-chromium, mercury, calcium, magnesium, lithium, sodium, potassium, zinc, and many more.

• NCERT Solutions for Class 8 Science Chapter 5: Coal and Petroleum

Carbon is one of the most important non-metallic elements. This is because all the bio-molecules invariably possess carbon and hydrogen as the major constituents. The special significance of carbon lies in the fact that it forms two types of compounds – organic and inorganic compounds. The compounds which are analogous to the corresponding compounds of other non-metallic elements are studied under the branch of inorganic chemistry. The chemistry of the wide range of the allotropic forms of carbon also comes in the realm of inorganic chemistry.

Occurrence-Carbon occurs in both free state and combined state. Carbon exists as the native element in the form of coal in the earth’s crusts. It occurs in a very small amount in its allotropic forms like diamond and graphite. Another form of carbon, fullerene, has been discovered by geologists in a crater made by a meteorite in Germany and ancient rocks in New Zealand.

Combined state

Carbon exists in the combined state in all the three physical states, namely solid, liquid and gaseous states.

•  Solid state:

Carbon occurs in the solid-state in the form of mineral carbonates like calcium carbonate (CaCO3), magnesite (MgCO3), Calamine (ZnCO3) etc. In plants and animals, carbon occurs in the form of fats, proteins, carbohydrates, and various other complex chemical compounds.

•  Liquid state:

Carbon commonly exists in a liquid state in fuels and vegetable oils. The fuels mainly comprise petrol, diesel, kerosene, LPG etc.

•  Gaseous State:

In a gaseous state, carbon exists either in the form of oxides, and hydrocarbons or in water as dissolved carbon dioxide. Carbon dioxide and carbon monoxide are the oxides of carbon. About 0.03% of the volume of the atmosphere is carbon dioxide while carbon monoxide is present in volcanic gases and furnace emissions of industries.

A wide variety of hydrocarbons occur naturally. The naturally occurring hydrocarbons are natural gas, petroleum gas, marsh gas and others. Carbon dioxide dissolves in water to form carbonic acid, which is present in all kinds of natural waters.

• NCERT Solutions for Class 8 Science Chapter 6: Combustion and Flame

The energy that is being transferred between two bodies as a result of temperature difference is called heat. Once it is transferred from one body to another body it becomes the internal energy of the receiving body. Heat is defined as long as the energy transfer is taking place. Heat in a body or heat contained by the body is meaningless.

Heat is the internal energy of the body. A hot body has more internal energy than an identical cold body. When a hot body is kept in contact with a cold body, the cold body warms up and the hot body cools down i.e., the

internal energy of the cold body increases and the internal energy of the hot body decreases. Thus heat is a form of energy which causes the sensation of hotness.

• NCERT Solutions for Class 8 Science Chapter 7: Conservation of Plants and Animals

1. Our planet has a rich variety of life but it is under threat because humans are using up more and more of the earth’s resources, producing more waste and causing more pollution.
2.  Plants and animals are disappearing or becoming endangered species at an alarming rate. Every few years, the international conservation union updates a list of species that are in danger of becoming extinct.
3.  Many animal species have either become extinct or are on the verge of extinction. This is because of continuous and constant exploitation by man.

Conservation of plants and animals is the practice of protecting them and their habitats. Wildlife conservation ensures that nature will be around for future generations to enjoy and recognize the importance of wildlife helping to implement policies designed to protect wildlife. Wildlife conservation has become increasingly important due to the negative effects of human activity on wildlife.

Many species of wildlife are disappearing fast and conservation measures are needed to prevent animals and plants from vanishing. Conservation is the planned management of a particular ecosystem or natural resources to prevent exploitation, pollution, and destruction and to ensure the future usability of the resources.

Wildlife represents all the non-cultivated and non-domesticated animals living in their natural habitats.

• NCERT Solutions for Class 8 Science Chapter 8: Cell Structure and Functions

Both living and non-living things are composed of molecules made from chemical elements such as Carbon, Hydrogen, Oxygen, and Nitrogen. The organization of these molecules into cells is one feature that distinguishes living things from all other matter.

The cell is the smallest unit of matter that can carry on all the processes of life. All living organisms carry out certain basic functions.

These functions are performed by the structural unit of an organ, called a cell. Any function performed by the organisms is the outcome of the activity of the cell. Before the 17th century, no one knew that cells existed since they are too small to be seen with the naked eye. The invention of the microscope enabled Robert Hooke, (1665) and Anton Van Leuwenhoek (1675) to see and draw the first ‘cells’, a word coined by Hooke to describe the cells in a thin slice of cork, which reminded him of the rooms where monks lived. In 1665, Robert Hooke, an English scientist while observing a dried section of cork (bark of a tree) with a crude microscope, observed small chambers in it and named them cells. Cork is a dead plant structure. He observed that the cork had several tiny compartments in it. He called these tiny compartments cells. However, the cell discovered by Hooke, was dead and only cellulose walls were visible.

Anton Van Leeuwenhoek (1974) was the first to observe living cells like bacteria, red blood cells and protozoa. Robert Brown (1931) reported the presence of a nucleus in root cells of orchids.

• NCERT Solutions for Class 8 Science Chapter 9: Reproduction in Animals

1. While individual organisms die without fail, species continue to live through millions of years unless threatened by natural extinction. Reproduction is the vital process which enables the species to survive for all these years. Reproduction is the creation of new individuals from previously existing individuals

        2. Reproduction is thus defined as a biological process in which organisms give rise to young ones (springs) similar to them. The offspring grows, matures and in turn produces new offspring. Thus, this cycle of birth, growth and death continues from generation to generation due to reproduction.

• Types of Reproduction

1.  Asexual reproduction
2.  Sexual reproduction

• NCERT Solutions for Class 8 Science Chapter 10: Reaching the Age of Adolescence

Topics covered in chapter 10 are reaching the age of adolescence, adolescence and puberty, changes at puberty, secondary sexual characters, the role of hormones in initiating reproductive function, the reproductive phase of life in humans, and how is the sex of the baby determined? hormones other than sex hormones, the role of hormones in completing the life history of insects and frogs, reproductive health

• NCERT Solutions for Class 8 Science Chapter 11: Force and Pressure

To open a drawer of the almirah, we need to pull the drawer. But when we want to close it, we have to push it with our hand. This signifies that an effort of ‘push’ or ‘pull’ is required to move a body.

So, Force is an external effort in the form of a push or pull acting on the body. Forces are used in our everyday actions like pushing, pulling, lifting, stretching, twisting and pressing.

EFFECTS OF FORCE

A force cannot be seen, tasted or felt. However, we can see or feel the effect of a force. A force can produce the following effects :

1.  A force can move a stationary body. E.g. a football at rest moves when it is kicked.
2.  A force can stop a moving body. For E.g. a moving car stops when the force of brakes is applied.
3.  A force can change the direction of a moving body. E.g. when a moving cricket ball is hit by a bat, the ball moves in a different direction due to the force applied by the bat.
4.  A force can change the speed of a moving body. For E.g. the speed of a falling ball increases because the earth applies a pulling force on it (force of gravity). Whereas, if the ball is thrown vertically upwards, the pull of the earth causes the speed of the ball to decrease.
5.  A force can change the size and shape of a body.

• NCERT Solutions for Class 8 Science Chapter 12: Friction

The force acting along the two surfaces in contact which opposes the motion or the tendency of motion of one body over the other is known as the force of friction or frictional force. It acts on both surfaces in contact.

Reason behind friction

Force of friction arises due to the force of adhesion at the point of contact. Adhesion is the force of attraction between molecules (material) of different kinds.

When two rough surfaces come in contact, many contact points are formed. The atoms or molecules present at such points of contact attract due to adhesive forces which oppose the motion of one body over another.

There are two areas of contact- apparent area of contact & actual area of contact.

Factors Affecting Friction

Friction depends on the following:

1.  Nature of surfaces.
2.  Normal forces (friction forces are directly proportional to normal force between the contact surfaces).
3.  Actual area of contact and the apparent (increases with increase in the actual area of contact).

• NCERT Solutions for Class 8 Science Chapter 13: Sound

A sound is a form of energy which makes us hear and travels in the form of waves. Sound is produced by various sources. Though the sound is mechanical, its perception is, of course, largely physiological.

The sound produced by vibrating objects reaches the listener only when it passes through a medium which may be a liquid, a solid or a gas. Let us now briefly discuss how sound travels from the source point of generation to the listener.

1. The vibration of the object sets the particles of the medium around it vibrating.
2. The particles do not travel from the vibrating object to the ear. A particle of the medium in contact with the vibrating object is first displaced from its equilibrium position as shown in the figure. This particle exerts a force on a neighbouring particle (2) which is displaced from its equilibrium position and also starts moving. After displacing particle (2), particle (1) comes back to its mean position. This process continues till the particle near the listener’s ear starts vibrating.

• NCERT Solutions for Class 8 Science Chapter 15: Some Natural Phenomena

In this chapter, we shall discuss two other destructive natural phenomena. These are lightning and earthquakes.

We shall also discuss what steps we can take to minimize the destruction caused by these phenomena.

LIGHTNING:

You might have seen sparks on an electric pole when wires become loose. This phenomenon is quite common when the wind is blowing and shaking the wires. You might also have seen sparks when a plug is loose in its socket. Lightning is also an electric spark but on a huge scale.

In ancient times people did not understand the cause of these sparks. They were, therefore, afraid of lightning and thought that the wrath of the gods was visiting them. Now, of course, we understand that lightning is caused by the accumulation of charges in the clouds. We need not be afraid of lightning, but we have to take precautions to protect ourselves from the deadly sparks.

The Sparks that the Greeks Knew

The ancient Greeks Knew as early as 600 B.C that when amber (amber is a kind of resin) was rubbed with fur, it attracted light objects such as hair. You might have seen that when you take off woollen or polyester clothes, your hair stands on ends. If you take off these clothes in the dark, you see even sparks and hear a crackling sound. In 1752 Benjamin Franklin, an American scientist, showed that lightning and the spark from your clothes are essentially the same phenomena. However, this realization took 2000 years. We shall now study some properties of electric charges. We shall also see how they are related to the lightning in the sky.

Benefits of NCERT solutions for class 8 Science

We are providing these solutions for free. Therefore, students can easily download a pdf of solutions for any chapter they want at no cost! They can look for offline solutions any time after downloading from our website. By referring to these solutions, they can easily solve all their doubts or questions. If they solve all the questions properly and understand the underlying concept in each question, they can easily get maximum marks in their examination.